September 26, 2012 -- A Slight Timeline Slip on a Program Already Way Ahead of Schedule

This morning Catalyst Pharmaceutical Partners announced that there would be a slight push-back in the timing on
the top-line data read for the Phase IIb trial of CPP-109 for the treatment of cocaine addiction. Originally, this
data was to be released in 1Q13 and then in July of this year, the company announced that the data would be
released earlier than expected, in late September.

The data is now expected to be released in the first half of November 2012. This is not a significant delay, in our
opinion, and is still much sooner than the originally planned 1Q13 timeframe.

Don’t Blame Catalyst

The current Phase IIb is being conducted in collaboration with the National Institute on Drug Abuse (NIDA) and
with the Veteran’s Affairs Cooperative Studies Program (VACSP) which are responsible for the management and
statistical analyses of the collected data from the study. The data has yet to be locked down as the VACSP still has
additional samples to analyze. We believe the analysis process is more complex than originally assumed by the
administration which gave the original late September timeframe for data availability to Catalyst and is now
amending it to the first half of November.

Focus on the Facts

The delay in announcing the top-line data is purely one of manpower and logistics and not one related to the
efficacy of CPP-109. The data will still be released well before year-end and some time before its originally
scheduled release of 1Q13. We continue to believe the data from CPP-109 will be positive and allow Catalyst to
potentially negotiate with the FDA to allow this trial to be a pivotal filing trial under the 505(b)(2) pathway.

The Phase IIb

The CPP-109 Phase IIb trial is a 24-week, randomized, double-blind and placebo-controlled study. It is designed to
demonstrate that the proportion of patients treated with CPP-109, who abstain from cocaine use in the last two
weeks of the trial's treatment phase, weeks eight and nine, will be greater than patients treated with placebo.
Other outcomes of the study include: a) the reduction in cocaine use days; b) the increase in clean urine samples
collected; and c) the durability of abstinence among those subjects who were abstinent during weeks eight and nine.